Question

Se sen x= 0,6 e XEIQ
Então calcule
Sen (2x)
Sen (3x)

Answer 1

Bom dia Gugui 

sen(x) = 0.6

sen²(x) + cos²(x) = 1
0.6² + cos²(x) = 1
0.36 + cos²(x) = 1
cos²(x) = 1 - 0.36 = 0.64
cos(x) = 0.8

sen(2x) = 2sen(x)*cos(x)
sen(2x) = 2*0.6*0.8 = 0.96 

sen(3x) = -4sen³(x) + 3sen(x)
sen(3x) = -4*(0.6)³ + 3*0.6 
sen(3x) = 0.936